Tube scraper



Aug. 17 1926. 1,596,065

K. MULLER TUBE SCRAPER Filed OC. 16. 1925 fi l In I V l y Patented ug. 17', j A @UNITED lsr.rlzlilzs :P Aram A`.OFfF-iCfEf .KURT .MLLER, or .-BEnNBUnesoN-THETSAALE, .ennMANx TUBE vSCRAIPFLBI.

Application 'filed 'October .16,

vThis invention relates to avtube :scraper i ldesigned to be :driven through .thetubes by radial direction, Asaid knife holders being loosely secured 'in said apertures.

Intubescrapersof this type knife holders are each one locked separately. According to the invention a locking device common to all knifeV holders is provided so that the taking to` pieces of the apparatus or the exchanging of the knives and the putting together are considerably facilitated.

An embodiment of the invention is shown by way of example in the accompanying drawing in which- Fig. 1 shows in axial longitudinal section the improved tube scraper to be operated by hydraulic pressure.

Fig. 2 is a. face view of the apparatus.

lFig. 3 is a face view of the end plate of the apparatus.

Fig. 4 is an end view of a clamping disk behind the end plate of the apparatus.

Fig. 5 is a section on line 5-5 of Fig. 1.

Fig. 6 shows a knife and its shaft viewed in radial direction from outside the apparatus.

Fig. 7 shows a constructional detail.

The apparatus` includes a circular end plate 1 (Figs. 1 and 3). At the centre of the end plate a rearwardly extending injection pipe 2 is arranged which is conically enlarged at the rear end. From the front face of the end plate 1 projects a cylindri-v cal extension 3 coaxial with said injection pipe and internally threaded. Into the threaded bore of the cylindrical extension 3` the threaded end 4.- of an eye may be screwed if necessary, to which eye a rope is attached.

The injection pipe 2 is externally threaded on its rear end. On this threaded rear end of the injection pipe the hollow internally threaded shaft 6 of an eye 7 is screwed to which a ro-pe can be attached. Radial slots 9, as shown in Fig. 3 eight slots, are arranged in the plate 1 in a circle around the central opening. The outer end walls of said slots are inclined in rearward direction. Behind the end plate 1 a ring 10 is arranged which has radial incisions 11 outwardly extending from its inner edge and registering with the slots 9 of the end plate 1, said ring serving to hold lamellae 12 for the packing.

1925, serial No. fsassaami in Germany August 5, v1924.

Airing 2O is pushed overthe rear end injection jpipe 2 said ring havin radial 'slotsl21with-rounded Iinner ends Fig. v5). This ri`ng20 is secured in position bythe hollow Yshaft 6 o'feye 7.

ofthe 'I The Lknife blades '22 which are 'inclined I in outward directional-e each fixed-by rivet-s on a 'base plate 24 on 4the front end of a knife shaft23. The lknife shafts 23 traverse eacha-set lof'slots 9, 1l and 21. IrThe cross section of the knife shafts 23 is rounded at t-he inner end and corresponds with the shape of slots 9 and 21. Each knife shaft 23 has, directly behind the end plate 1, an

inwardly projecting nose 31 designed to shut off the free inner portion of the slot 9 when the knife shaft is swung in outward direction. The outer face of the knife shafts is shaped in accordance with the inclined outer ends of slots 9. A groove 25 near the rear end of each knife shaft 23 is slightly longer than the ring 20 is thick. ln radial direction the hookshaped rear ends of the knife shafts formed by the grooves 25 are of such dimension that when the hollow shaft 6 of eye 7 has been removed they can easily pass through the slots 21 so that the knives can he easily removed. When the veye is screwed on, the end of its shaft 6 overlaps the lower ends of slots 21 so that the ends of the knife shafts 23 can not be moved in inward direction suiiiciently to remove the knife shafts through said slots. The eye 7 or its shaft 6 locks the knife shafts in their position.

Radially arranged spiral springs 29 inserted between the ends of the knife shafts and the cylindrical extension 3 of the end plate serve to press the knife shafts in outward direction. Rollers 2S on the front ends of the knife shafts slide on the inner wall of the tube. The spiral springs 29 are located in cylindrical cavities 30 of the knife shafts.

A conical nozzle y32 is inserted into the front end of the injection pipe 2 and held in position by the hydraulic pressure. To exchange the nozzle 32 against a nozzle of other diameter the nozzle is pushed out to the rear with the aid of any suitable implement.

Owing to its conical shape the nozzle 32 is sufficiently clamped in the injection pipe so that when the apparatus is brought out of the horizontal position the nozzle cannot drop out of the injection pipe, a stop pin 33 being arranged in the rear portion of the injection pipe to further prevent the nozzle from dropping out. The nozzle when it should have moved from its seat Will be automatically returned to the proper position by the hydraulic pressure.

.I claim 1. A tube scraper comprising in combination an end plate having` a conical central opening and radial slots, a rearwardly projecting injection pipe conical at the front end and merging with said central opening and enlarged at the rear end, an annular plate on the rear side of said end plate and having radial slots, a ring on the rear end of said injection pipe having radially arranged slots7 knife shafts inserted through the slots of said plates and having hook-shaped rear ends hooked through said ring slots, a cylindrical shaft screwed on the rear end of said injection pipe and locking said hook-shaped ends in position, an eye on said cylindrical shaft to Which eye a rope may be attached, a cylindrical central extension on the Jfront side of said end plate,'spiral springs inserted between said cylindrical extension and each knife shaft for pressing the same in outward direction, an inclined knife on the front end of each ,knife shaft, anda roller in the front end of each knife shaft designed to roll on the inner wall of the tube to be scraped f.

ln a tube scraper of the type claimed a-conical nozzle loosely inserted in the front en'l of said injection pipe.

ln testimony whereof I afIiX my signature.

KURT MLLER. 

